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PubMed2000

Impairment magnification during dynamic trunk motions.

STUDY DESIGN: An examination of a group of patients with low back disorder and a group of healthy (asymptomatic) individuals asked to produce trunk motions under sincere and insincere experimental conditions. Trunk motion components were examined to determine which combination of motion components could best distinguish between sincere and insincere efforts. OBJECTIVE: To determine whether examination of trunk motion components could be used to identify impairment magnification during unresisted repeated bending tasks. SUMMARY OF BACKGROUND DATA: Trunk motion measures can be used to assess and "benchmark" the status of the low back. However, these measures typically are clinically useful only if the individual is producing an effort that does not magnify the impairment during the functional evaluation. This study addressed the issue of impairment magnification during the production of free dynamic trunk motion. METHODS: The trunk motion characteristics of 100 healthy individuals and 100 patients with chronic low back disorders were documented. All participants were asked to produce the trunk motions in two different types of conditions. In the one experimental condition, they were asked to produce sincere trunk motions. In the other experimental condition they were asked to pretend either that they were experiencing low back pain (the asymptomatic group) or that their pain was worse than it actually was (group with low back pain). RESULTS: A combination of trunk motion measures was able to distinguish well between the conditions. Sensitivity and specificity for the asymptomatic group were 92%, whereas they were 75% for the group with low back pain. Overall, sensitivity and specificity were 81.5% for all the participants combined. CONCLUSIONS: These results indicate that motion measures can be used to help assess impairment magnification during functional trunk motion testing. These measures can provide a means by which to scrutinize the quality of quantitative measures indicating the extent of a low back disorder. These objective motion measures also can be used to complement other subjective observational methods for the assessment of impairment.

Acceleration↗
PubMed1984

An apparent paradoxical effect of pretransplant blood transfusions. Its association with decreased anti-HLA antibody formation following unsuccessful renal transplantation.

Many potential renal transplant recipients develop multispecific anti-HLA antibodies after a previous unsuccessful transplant. Therefore, it became important to analyze factors that could predispose to multispecific anti-HLA antibodies in the hope of preventing their occurrence because their presence hinders early retransplantation. In these studies, we elected to retrospectively analyze the impact of previous transfusions and the degree of HLA-A,B antigen mismatch on the development of these antibodies. Patients transplanted within the South Eastern Organ Procurement Foundation ( SEOPF ) after January 1977 were analyzed. All patients in these studies were immunosuppressed with prednisone and azothioprine . Antibodies to HLA antigens were determined in a complement-dependent microcytotoxicity assay utilizing recipient's sera and lymphocyte cell panels from random donors. Multispecificity of antibody was quantitated and expressed as the percentage of reactivity to lymphocyte panel (PRL). Only patients who lost their first cadaveric kidney allograft, and who, in addition, had a peak of less than 15% pretransplant and no prior pregnancies were analyzed. Peak posttransplant PRL had to be determined within 3 months after allograft failure. In the 146 patients with accurate transfusion data, it became evident that patients who received more than 5 pretransplant transfusions seldom developed greater than or equal to 50% PRL posttransplantation (P less than 0.001). Only 12% of patients receiving more than 5 pretransplant transfusions developed greater than or equal to 50% PRL, whereas 50% of patients with minimal pretransplant transfusions developed greater than or equal to 50% PRL. This protective effect of pretransplant transfusions was seen even in recipients receiving 3 and 4 HLA-A,B mismatched kidneys (P less than 0.01). The reason for this apparent protective effect is not clear from our data; it could be explained either on the basis of a selection process (i.e., exclusion of high responders pretransplant) or by suppression of the immune system. Nonetheless, these observations warrant attention, because the protective effect may be useful in preventing development of high PRL posttransplant in the event of a rejection.

Antibody Specificity↗
PubMed1995

Mechanism of human polymorphonuclear leukocyte adhesion to serum-treated corneocytes.

The accumulation of polymorphonuclear leukocytes (PMN) beneath the stratum corneum is a characteristic histopathologic finding in various aseptic pustular dermatoses. To elucidate the pathomechanism involved in this phenomenon, we investigated whether PMN also attach to a sheet of corneocytes in vitro. A 1-cm2 corneocyte sheet was attached to a sterile glass slide with double adhesive tape used for skin graft surgery before incubating with human serum. The PMN suspension then was applied to the sheet. Attached cells were stained with May-Grunwald-Giemsa and counted with a computer image analyzer. We quantitatively assessed PMN adhesion to the serum-treated corneocyte sheets, which was mediated by activation of the alternative complement pathway. Addition of either anti-CD18 or anti-CD11b antibody to the assay system resulted in a marked reduction of PMN adhesion. We also demonstrated immunohistochemically that iC3b was formed on the serum-treated corneocytes. These findings suggest that PMN attach to serum-treated corneocytes through an interaction of CR3 expressed on PMN with iC3b-coated corneocytes. In addition, we found that this adhesion was enhanced by activation of PMN with phorbol myristate acetate. From these results, we speculate that complement activation by corneocytes occurs in the cutaneous lesions of aseptic pustular dermatoses and that PMN can be stimulated by the interaction with iC3b-opsonized corneocytes as well as by chemotaxins, leading to damage of the surrounding epidermal keratinocytes.

Blood Physiological Phenomena↗
PubMed1983

Computer graphic representation of mandibular movements in three dimensions: the method.

A mathematical simulation of the Denar D4A articulator and a simulated complement of graphically represented teeth were programmed in a Prime 4000 minicomputer. The computer program could be manipulated to quantitatively evaluate the theoretical effects of changes in articulator and control factors on the anatomy of selected teeth or tooth groups. The effects of these changes could be assessed graphically and numerically and data could be manipulated statistically.

Dental Articulators↗
PubMed2005

Plastid division is mediated by combinatorial assembly of plastid division proteins.

Plastids arise by division from pre-existing organelles, and with the recent characterization of several new components of plastid division our understanding of the division process in higher plants has improved dramatically. However, it is still not known how these different protein components act together during division. Here we analyse protein-protein interactions between all known stromal plastid division proteins. Using a combination of quantitative yeast two-hybrid assays, in planta co-localization studies, fluorescence resonance energy transfer and bimolecular fluorescence complementation assays we show that these proteins do not act in isolation but rather in protein complexes to govern appropriate plastid division. We have previously shown that AtMinD1 forms functional homodimers and we show here that in addition to homodimerization AtMinD1 also interacts with AtMinE1. Furthermore, AtMinE1 has the ability to homodimerize. We also demonstrate that proteins from both FtsZ families (AtFtsZ1-1 and AtFtsZ2-1) not only interact with themselves but also with each other, and we show that these interactions are not dependent on correct Z-ring formation. Further to this we demonstrate that ARC6 specifically interacts with the core domain of AtFtsZ2-1, but not with AtFtsZ1-1, providing in planta evidence for a functional difference between the two FtsZ protein families in plants. Our studies have enabled us to construct a meaningful intraplastidic protein-protein interaction map of all known stromal plastid division proteins in Arabidopsis.

Arabidopsis Proteins↗
PubMed1983

Enzyme-linked immunosorbent assay for detection of measles antibody.

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of measles immunoglobulin G antibody (MEASELISA). This assay was found to be comparable to the measles hemagglutination inhibition (HAI) test. Approximately 500 sera from three centers were tested by MEASELISA and the HAI test. MEASELISA demonstrated values of greater than 99% for sensitivity, specificity, and accuracy. Values were very precise, with a mean coefficient of variation of 5.4%. MEASELISA values were shown by linear regression analysis to increase as HAI titers increased. A coefficient of determination of 1.00 was obtained from test center three. MEASELISA values were found to be linearly related (r2 greater than 0.97) to MEASELISA titers, thus enabling quantitation of measles antibody from a single value. Also, data are presented that show MEASELISA to be equivalent to complement fixation for evaluating paired sera for the presence of a significant increase in antibody levels to measles virus.

Antibodies, Viral↗
PubMed2005

Positron emission mammography: high-resolution biochemical breast imaging.

Positron emission mammography (PEM) provides images of biochemical activity in the breast with spatial resolution matching individual ducts (1.5 mm full-width at half-maximum). This spatial resolution, supported by count efficiency that results in high signal-to-noise ratio, allows confident visualization of intraductal as well as invasive breast cancers. Clinical trials with a full-breast PEM device have shown high clinical accuracy in characterizing lesions identified as suspicious on the basis of conventional imaging or physical examination (sensitivity 93%, specificity 83%, area under the ROC curve of 0.93), with high sensitivity preserved (91%) for intraductal cancers. Increased sensitivity did not come at a cost of reduced specificity. Considering that intraductal cancer represents more than 30% of reported cancers, and is the form of cancer with the highest probability of achieving surgical cure, it is likely that the use of PEM will complement anatomic imaging modalities in the areas of surgical planning, high-risk monitoring, and minimally invasive therapy. The quantitative nature of PET promises to assist researchers interested studying the response of putative cancer precursors (e.g., atypical ductal hyperplasia) to candidate prevention agents.

Breast Neoplasms↗
PubMed1984

Effect of ACTH on endogenous steroid biosynthesis in long-term primary cultures from newborn rat adrenal cells.

Normal newborn rat adrenal cells kept in primary culture up to 2 1/2 months respond to ACTH stimulation and produced corticosteroid hormones and smaller amounts of 20 alpha-reduced progesterone metabolites. Cholesterol from the serum complemented culture medium serves as precursor without further addition of exogenous steroid substrates. A long-term qualitative and quantitative study of individual steroid production under the influence of ACTH was performed. ACTH treatment produced a triphasic effect on steroid production: an induction period (up to 3 days), an acute maximum production period (3rd to 6th day) and a chronic production period (to the end of the treatment). The increase in total steroid production resulted from the increase in the production of corticosteroids only. This indicated an increase of cholesterol side-chain cleavage and of the 21- and 11 beta/18-steroid hydroxylations. Removal of ACTH led to a reversible drop in total steroid production. The response to ACTH was dose dependent, so that a 2.2 mU/ml dose elicited lower steroid production than the 6.6 or 22 mU/ml doses. Increasing the lower dose after a week of treatment to a higher dose brought total steroid production and 11 beta/18-steroid hydroxylation up to the corresponding chronic production levels. The 20 alpha-steroid reduction system was not affected by ACTH. ACTH changes the importance of the two main steroidogenic pathways. With no ACTH there is approximately a 1:1 ratio between corticosteroid synthesis and progesterone reductive metabolism; a low dose of ACTH increases the total steroid production, but since corticosteroid production and 20 alpha-reduced metabolites both increase, the ratio changes little; a high dose of ACTH increases the ratio to more than 30:1. Refractoriness or desensitization to ACTH is postulated to occur through the control of cholesterol availability inside the cell possibly combined with a control of its utilization for steroidogenesis.

Adrenal Cortex Hormones↗
PubMed2002

Comparison of uteroplacental glycosylation in the camel (Camelus dromedarius) and alpaca (Lama pacos).

The recent birth of a camel-llama hybrid, after numerous failed attempts, has prompted an investigation into the glycosylation of apposing fetal and maternal tissues of pregnant camels and alpacas. This study was undertaken to determine whether interspecies differences in glycans are factors that may account in part for the difficulty in producing a viable hybrid. Specimens of camel placentae from day 60 to day 375 of gestation and alpaca placentae from day 22 to term (approximately 345 days) were fixed and embedded in resin, and sections were stained with a panel of 19 biotinylated lectins and an avidin--peroxidase revealing system. Several qualitative interspecies differences in tissue glycosylation were found, mainly in the trophoblast, and especially with respect to bi/tri-antennary bisected N-glycan, fucosylated structures, beta-galactosyl residues and sialyl termini. In the maternal uterine epithelium, differences were found mainly in bi/tri-antennary bisected complex N-glycan and beta-galactosyl residues, indicating that there is more conservation of glycosylation in maternal tissues compared with trophoblast. There were also many quantitative differences in the distribution of glycans. It is possible that a failure to effect the normal glycan--glycan complementation that occurs at the cell surface between maternal and fetal tissues during the implantation processes of apposition and adhesion may account in part for the difficulty in establishing a viable pregnancy between these two species.

Animals↗
PubMed2005

[Screening of differentially expressed genes in colorectal cancer using human whole genomic oligonucleotide microarrays].

OBJECTIVE: To screen the differentially expressed genes in human colorectal cancer (CRC) tissue. METHODS: Affymetrix oligonucleotide microarrays HG-U133 representing 32,264 human genes including 19,308 known genes and 12,956 expressed sequence tags (ESTs) were used to detect the gene expressions of CRC tissue paired with normal mucosa tissue. The microarray findings were confirmed by real-time quantitative reverse transcriptase-polymerase chain reaction (FQ-PCR). The gene expression profiles were analyzed by intersection and complement, rank sum test and t test. RESULTS: Totally 3,125 genes and ESTs expressed differentially were detected in normal and cancer tissues, consisting of 974 up-regulated and 2,151 down-regulated genes with 247 ESTs present in CRC tissue and absent in normal mucosa and 162 ESTs absent in CRC tissue but present in normal mucosa. A percent of 80.1% of the differentially expressed genes were not reported in the literatures. CONCLUSION: The strategy of data mining provides a foundation for filtering molecular markers and interpreting molecular carcinogenesis of CRC.

Colorectal Neoplasms↗
PubMed1987

Human T cell subset ratio quantitation by 51Cr release: assessment of a new technique.

A method for T cell subset ratio quantitation is described. This technique makes use of monoclonal antibodies 66.1 (OKT4 equivalent) and 51.1 (OKT8 equivalent) in complement-dependent cytotoxicity. The percentages of 51Cr release with these 2 reagents from peripheral blood lymphocyte targets were used to calculate the ratio. It is simple, inexpensive, and can be used for large numbers of samples, but is less accurate when compared with the microscopic technique in immunofluorescence. It may serve as a screening test in certain clinical situations where there is need to determine the T4/T8 ratio.

Antibodies, Monoclonal↗
PubMed1983

[Laboratory procedures with adenoviruses. IX. Hexon antibody determination by countercurrent immunoelectrophoresis].

101 paired sera from patients with proved adenovirus infections (mostly conjunctivitis) were tested quantitatively by counter immunoelectrophoresis, with hexon of adenovirus 5 as a genus-specific antigen, in comparison with complement-fixation. Both methods were equally sensitive to demonstrate antibodies; also the titers showed a marked correlation. The number of titer rises, however, was higher in counter immunoelectrophoresis; the titer rises mostly occurred around the 10th day after onset of disease. No differences between patients infected with different adenovirus types were found.

Adenoviridae Infections↗
PubMed1984

[The striated sphincter of the urethra. 3: Urodynamic and physiopathologic study of the striated sphincter].

Dysfunction of the rhabdosphincter results from an increase (dyssynergia) or decrease in activity of either neurological or non-neurological origin. We have defined dyssynergia as the absence of urethral relaxation and/or sphincter contraction during and/or before detrusor muscle contraction. Non-invasive exploratory methods include flowmetry, anal contact EMG and an abdominal pressure or EMG examination. Invasive techniques are of various types: urethro-cystometry with EMG, via the perineum in males and the endo-urethral approach in females, provides quantitative data on extent of altered function and relative involvement of either smooth or striated muscle sphincters. An essential complement to urodynamic exploration is a conventional mictional cystogram. We have proposed an etiologic classification of dyssynergia: tonic dyssynergia is pathognomonic of supra-sacral medullary lesions while clonic dyssynergia reflects the bladder-sphincter conflict, whether it be of neurologic or other origin. Clonic dyssynergia in patients with neurologic affections is seen mainly in those with supra-sacral medullary lesions at whatever level, and with a 50 to 100% frequency. Its serious nature is not related to the bladder-sphincter equilibrium but to the high pressures developed by the system. The neurologic rhabdosphincter presents characteristic persistent reflex activity at the spinal shock phase and a possible course leading to fibrosis. In patients without neurologic disease the terms dyssynergia or pseudodyssynergia are used depending on whether the sphincter contraction during bladder contraction is involuntary or voluntary. To explain this non-neurologic pseudodyssynergia, Lapides suggested as a basis the theory of the evolution of sphincter control, Tanagho that of sphincter spasticity. In reality it involves a vicious circle centered on the bladder-sphincter conflict, entry being possible at various levels: bladder instability, urethral instability, urethral hypersensitivity, rhabdosphincter spasticity. These disturbed functions induce the urethral syndrome, repeated urinary infections, reflux and sometimes even renal stasis. Deficient sphincter activity of neurologic origin presents pathognomonic electromyographic signs; from a functional point of view valid data can be obtained from measurement of variations in maximum urethral pressure during a retention effort. Among the neurologic etiologies, the rhabdosphincter is only rarely affected by poliomyelitis or amyotrophic lateral sclerosis.(ABSTRACT TRUNCATED AT 400 WORDS)

Ataxia↗
PubMed1984

[Hereditary angioneurotic edema: a molecular disease caused by a defect in the O-glycosylation of C1 esterase inhibitor (C1-INH)].

A quantitative and qualitative study of neutral and aminosaccharides in C 1-esterase inhibitor (C 1-INH), protein of the complement system, was performed. We observe a mixed glycosylation of the molecule with an N-glycosylated: O-glycosylated chain ratio of 1: 4. The loss of the inhibitory activity of the molecule in hereditary angioedema (O ANH) is associated with an O-glycosylation deficiency which differs according to the two molecular variants: C 1-INH (1 A) and C 1-INH (II) previously described.

Angioedema↗
PubMed1984

Saturday night live: chronicity of alcohol consumption among college students.

Through means of a daily diary, alcohol consumption patterns of students at a major metropolitan university were studied. Drinking displayed a weekly pattern which reflected student role demands, but was also influenced by family roles, external events, and fluctuations in academic pressures. There were distinct patterns in both percentage of students drinking and in mean ethanol consumption per drinker. There was also a clear pattern of "binge" drinking in the aftermath of stress. Drinking in the campus context was both quantitatively and qualitatively different from drinking in the family context. Chronographic analysis provides a key to understanding behavior which complements cross-sectional or longitudinal panel analysis.

Adult↗
PubMed1993

Complement-mediated binding of naturally glycosylated and glycosylation-modified human immunodeficiency virus type 1 to human CR2 (CD21).

Particulate glycoproteins lacking sialic acid, such as desialylated enveloped viruses, readily activate complement through the alternative pathway. Human immunodeficiency virus type 1 (HIV-1) contains two heavily glycosylated and partially sialylated envelope glycoproteins: a surface gp120 and a transmembrane gp41. The abilities of naturally glycosylated HIV-1 and glycosylation-modified HIV-1 to interact with the complement system were examined with a biological assay which measured the binding of whole virus particles to cells expressing CR2 (CD21), the complement receptor found naturally in abundance on follicular dendritic cells and immature B cells. HIV-1 IIIB was synthesized in the presence or absence of the mannosidase II inhibitor, swainsonine, to give rise to high-mannose-type, nonsialylated, nonfucosylated carbohydrate moieties. The virus also was treated with neuraminidase or endo-beta-galactosidase to remove terminal sialic acids. An enzyme immunoassay specific for HIV-1 p24 core protein was used to quantitate the amount of virus bound to cell surfaces. Virus particles incubated with 1:3-diluted, fresh HIV-1-negative human serum as a source of complement readily bound to MT-2 (CD4+ CR2+) and Raji-3 (CD4- CR2+) cells but not to CEM (CD4+ CR2-) cells, suggesting that the virus bound to CR2 independently of CD4. Compared with heat-inactivated or C3-deficient sera, fresh complement increased binding by as much as 62 times for naturally glycosylated virus, and 5 times more than this for glycosylation-modified virus. Similar observations were made with freshly isolated, non-mitogen-stimulated peripheral blood mononuclear cells. Additional evidence that HIV-1 bound to CR2 independently of CD4 was provided by the fact that binding was blocked by monoclonal antibody OKB7 (anti-CR2) but not by OKT4a (anti-CD4). Also, the virus bound to transfected K562 cells (CD4-) which expressed recombinant human CR2 but did not bind to untransfected K562 cells. Results obtained with complement component-deficient sera indicated that binding required the alternative complement pathway. Raji-3 and transfected K562 cells could not be infected with HIV-1 in the presence of complement, suggesting that utilization of CR2 as a receptor in the absence of CD4 does not allow virus entry. The demonstration of CR2 as a receptor for HIV-1 in the presence of complement, together with the ability to enhance binding by desialylation, provides new insights into mechanisms of HIV-1-induced immunity and immunopathogenesis.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Quantification of non-activated (native) complement component C9 synthesized by alveolar macrophages from patients with sarcoidosis.

Alveolar macrophages (AM) from sarcoidosis patients synthesize the functional alternative and terminal pathways of complement, and increased complement production may be one of multiple factors in the pathogenesis of sarcoidosis. We thus examined whether AM from sarcoidosis patients produced quantitatively more C9 in vitro than AM from healthy controls. AM from 16 patients with active sarcoidosis and seven healthy controls were cultured under serum-free conditions for 6, 12, 24, 48, or 72 h. A quantitative production of C9 was found in the harvested medium in 10 of 16 sarcoidosis patients. There were no detectable levels of C9 in the seven controls. Activated C9 was found in all patients and in the majority of the controls. C9 was quantified by an enzyme immunoassay based on a monoclonal antibody (M1) to non-activated C9. Our results indicate greater production of C9 by sarcoidosis AM than by their healthy counterparts.

Adult↗
PubMed1984

Binding of complement subcomponent C1q to mouse IgG1, IgG2a and IgG2b: a novel C1q binding assay.

A C1q binding assay is presented which is suitable for use in comparison of the binding ability of different antibodies, and which allows the quantitative determination of their binding constants. The assay system uses IgG bound to a hapten-derivatized Affigel support. No non-specific binding is observed to a DNP-derivatized support, allowing the use of anti-DNP antibodies. With mouse anti-DNP hybridoma IgGs it was found that C1q binding followed the series IgG2a greater than IgG2b much greater than IgG1, in accordance with the complement fixing ability of these subclasses. Since it is relatively simple to couple any antigen to Affigel , this assay system should be generally applicable to any antibody-antigen system.

2,4-Dinitrophenol↗